System for displaying coded information on cathode ray tubes



H. W. VOLBERG Feb. e, 1962 SYSTEM FOR DISPLAYING CODED INFORMATION ON CATHODE RAY TUBES Filed Aug. 4, 1958 Feb. 6, 1962 H. w. voLBERG SYSTEM FOR DISPLAYING CODED INFORMATION ON CATHODE RAY TUBES 2 Sheets-Sheet 2 Filed Aug. 4, 1958 INVENTOR HERMAN W l/oLBE/zG. f/JWM o m mI-U-IH- o N atei E Patented Feb. 6, 1562 fee 3,020,530 1 SYSTEM FOR DISPLAYlNG CODE!) INFORMA- 'HON 0N CATHDE RAY TUBES Herman W. Valberg, San Diego, Calif., assigner to Generai Dynamics Corporation, Rochester, N.Y., a corporation of Delaware Fiiet Aug. 4, 1958, Ser. No. 753,032 12 Claims. (Cl. 340324) The present invention relates to a system for displaying coded information in the form of characters on cathode ray display means. More particularly, it pertains to a circuit, and waveform generating units capable of receiving and decoding incoming code information, transforming the coded information into coniigurated waveforms through semi-conductor waveform generating units, and supplying the waveforms to cathode ray display means causing predetermined character images to be displayed in accordance with the logic of the incoming code.

In using present-day computers and similar type systems for processing data and providing output information in the form of analog or binary logic, it is often desirable to readout or display the output logic in the form of character images on cathode ray tubes. Systems presently used for this purpose are quite complex and expensive. Therefore, it is of an obvious advantage to have a simplified system.

It is accordingly an object of this invention to provide a simple and relatively inexpensive system of displaying high speed electronic code information in the form of characters on cathode ray tube display means.

Another object of the invention is to provide a system displaying high speed electronic code information in the form of characters on cathode ray tube display means having a rugged construction, long life and a relatively small size.

It is another object of this invention to provide a system of the type disclosed with a synchronized unblanking control and a variable intensity modulation of the electron beam.

It is another object of the invention to provide a system that displays high speed electronic code information in a format arrangement.

It is also an object of this invention to provide a system that displays high speed electronic code information in the form of variable character sizes.

It is a further object of this inventionto provide a waveform generating unit in a system of the type disclosed capable of driving any number of conventional type cathode ray tubes.

In accordance with the present invention, coded information in the form of analog, binary or other forms having a particular alphabetic or numerical character designation is supplied to an appropriate decoding circuit. The circuit decodes the input information disseminating it in the form of pulses to circuit channels corresponding to particular characters to be displayed by the cathode ray display means. Output pulses from the channels are thereupon employed to energize waveform generating units for generating coniigurated waveforms. These units comprise individual semi-conductor units, each of which is capable of providing a predetermined congurated waveform output that, when impressed on the cathode ray display means, will cause a predetermined character to be written or drawn on the cathode ray display means. The congurated waveform outputs of any one waveform generator combine to control the deflection of the electron beam in a manner causing the electron beam spot to be deflected tracing out each desired character smoothly and continuously. Y

The system provides apparatus'capable of high speed presentation of any desired character Lorconigurated form having any desired size consistent with the size of the tube screen. It is also capable of providing synchronized unblanking of the beam generating means in the cathode ray display means for desired synchronized energizing, interrupting and shutting off of the display. The unblanking `unit is also capable of providing intensity modulation of the display thereby permitting portions of the character displays to be shaded if desired. The waveform generating units may be energized by an interrogation pulse for each character to be displayed, and the waveforms generated therefrom may be used to drive in synchronism any number of cathode ray tubes for displaying similar information. The system has a minimum number of electrical components rendering it relatively inexpensive and simple to construct for systems of this type. Further, the type of components of which it is possible to use in the systems permits a small, compact and easily made portable unit. The system of the invention may be used with conventional cathode ray tubes, known in the art and may also include a built-in format generating device.

The exact nature of this invention as well as other objects and advantages thereof will be readily apparent from consideration of the following specitication relating to the drawings, in which:

FIGURE 1 is a circuit schematic diagram of the present invention;

FIGURE 2 is a graphic illustration of the 6-bit binary code arrangement for characters to be displayed on the screen of the cathode ray tube;

FIGURE 3 is a perspective view with accompanying circuitry of a waveform generator for use in the present invention;

FIGURE 4 is a graphic illustration of the relationship of the waveforms generated by a waveform generator in causing the cathode ray tube to display a predetermined character.

Referring more particularly to the drawings, like reference numerals refer to the same parts throughout the several views. In FIGURE l, a specific embodiment of the invention is shown comprising a decoding circuit 10 for decoding incoming code information. This circuit provides output pulses to particular lines connected to individual waveform generators, which generators correspond with the character designation attributable to the incoming code. The decoding circuit may be made capable of decoding any form of code information as for eX- ample, binary or analog or the like.

In the embodiment, decoding circuit l@ is capable of decoding 6-bit binary information and disseminating it to a circuit network in accordance with its attributable character designations. It receives the incoming 6-bit binary information of either positive or negative polarity at input lines A, B, C, D, E and F. Each of the incoming binary bits pass to a parallel circuit, as for example, the binary bit received by line I9 provides a potential output to line A1 having the same positive or negative potential as that received by input line A. The incoming pulse supplied to line A2 passes through the inverter unit 18,

. stantially short circuited condition between emitter and collector providing a positive output pulse. When a .positive pulse of greater magnitude than the positive emitter potential is fed to the base, the transistor is then cut oi, causing a negative output pulse to be supplied to output line 82, or, in this instance, A2 from negative voltage source 9i). Accordingly, lines A1, B1, C1, D1, E1, and F1 all carry output pulses having of a polarity identical to that received from lines A, B, C, D, E and F, while lines A2, B2, C2, D2, E2 and F2 carry output pulses of a polarity opposite to that received by the incoming lines.

Each of the and gates 22 are also identical and of conventional design. They each have a uni-directional device in each of their six input lines. The uni-directional devices are positioned in each of the incoming lines to pass only a positive potential tc the common output line 45. As is well known in the art, and gate 22 will provide an output pulse to common output line 45 only when each of the incoming lines connected thereto simultaneously carry a positive pulse. Each group of binary code pulses represent a particular character through the arrangement of the positive and negative pulses in the 6-bit code group. Also, each and" gate 22 is responsive to only one particular code group in relation to its character designation. The network of connecting lines between the receiving portion of decoding unit 10 and the and gates 22 are so arranged and interconnected as to provide positive pulses in each of the lines connected to the particular and gate to be energized by a corresponding incoming binary code group.

In FIGURE 3, the positive and negative bits of the binary code for energizing the particular and gates identified with numerals 1 through 5 are set forth. The invention is capable of reading out as many characters as desired, and there would accordingly be a code group and an and gate for each individual character. Lines D1, E1 and F1 shown at 23 would lead to such other and gates as would be desired. As aforesaid, there is an and gate for each character to be displayed on the screen of the tube in response to the incoming code and accordingly, a network of lines from each of the incoming lines A, B, C, D, E and F would be connected to all the and gates in a manner similar to the network of lines connected to the and gates shown. For purposes of simplicity, only a representative portion of the and gates are illustrated.

Wave form generating units 25, 26 and 27 each generate waveforms which when supplied to the deflection means 50 in cathode ray tube 54, will cause the respective numerals 1, 2 and 3 to be Written on the screen of the cathode ray tube. Each waveform generating unit operates independently of the rest and when receiving a positive interrogating pulse from its respective and gate, will cause a single predetermined character to be displayed on the tube screen. The waveform generating units may take a form as illustrated in FIGURE 4 and as disclosed in detail in applicants copending application Serial No. 753,031, assigned to the common assignee hereof.

Each unit comprises a body or block 60 of semi-conductor material. Block 60 has a general rectangular configuration with a truncated portion 63 giving an inclined surface to the upper portion that is at an angle with at or bottom portion 62 of the block 60. The block 60 being of semi-conductor material, may take the form of either P type or N type material such as P type germanium or silicon, or the like, or, N type germanium or silicon or the like, or, it may be of intrinsic semiconductive material. The general properties required of the material is that they have current carriers therein, or, be capable of having current carriers therein which will drift through the material in the form of a relatively thin planar sheet or in a pocket having a relatively small dimension in response to an interrogation pulse.

The block 6) shown in FIGURE 3 consists of N type material 86 which forms a major part of the block with P type germanium or silicon material attached to the bottom side thereof as shown at 61, in a manner well known in the art of joining such substances together. An ohmic coating contact covers the bottom surface 62 of the block 60. On the upper surface of the block 60, the inclined portion 63 is substantially covered with ohmic material being interrupted by the insulated congurated conductor portions 70, 71 and 72. The congurated conductor portions form predetermined congurated areas which are also covered with ohmic material, but which are separated from the other ohmic coated surfaces on the surface 63 in the manner shown by insulated border portions 69. Each of the configurated conductor portions 76, 71 and 72 are connected to separate output lines 75, 76 and 77.

Contact 64 and line 78 are connected through a limiting resistor 67 to a variable voltage source Vf shown as 24. Voltage source Vf creates a sweeping field through the block by way of inclined surface 63 and the bottom surface 62. Positive interrogation pulses are supplied to the unit 60 by means of line 47 through D.C. blocking capacitor 66.

In operation, the waveform generating unit provides a configurated waveform output in substantially the manner as follows. An interrogating pulse 79 is supplied to line 47 through D.C. blocking capacitor 66 to contact the ohmic coating 64 at the bottom 62 of the block 60. This positive pulse when applied to the P type semi-conductive material 61 causes holes to be injected into the N type material which comprises the majority portion of the block. The holes are injected into the N type material 80 in the form of a relatively thin planar sheet 73 encompassing the entire cross sectional area of the block. The thickness of the sheet of holes 73 at the point of initial injection is generally dependent upon the length of the positive square wave pulse 79 and the pulse amplitude. Following the injection of the sheet of holes into the N type material, the sheet of holes drifts in a predetermined manner towards the inclined surface 63 -in response to the sweeping tield created by the variable voltage source 24. The speed of drift of the sheet of holes or current carriers 73 toward the inclined surface is dependent upon the strength of the eld. The Vf voltage source 24 includes. means for varying the strength of the sweeping eld thereby permitting the time required for the sheet of current carriers to traverse the length of the semi-conductor materials to be select-ively varied. The sheet of current carriers 73 drift in a direction substantially perpendicular to the bottom surface 62 in response to the sweep-- ing field while maintaining a substantially planar relationship to the bottom surface 62. As a result, the sheet of current carriers 73 intersect the overall area of the yinclined surface 63 in successive time intervals contacting the nearest portion first and contacting the furthest portion from the bottom surface 62 last. Accordingly, the sheet of current carriers progressively contact the entire inclined surface 63 and the conigurated portions 70, 71 and 72 by stages relative to time. The holes or current carriers in the sheet 73, which contacts that portion of the surface 63 outside the insulated configurated portion, returns to the voltage source Vf through connecting line 30.

The current carriers successively contacting the configurated conductor portions 70, 71 and 72 create the output waveforms in their respective connecting lines 75, 76 and 77. At any one instant of time during the intersection of these contigurated portions by the sheet of current carriers, the magnitude of the respective output waves correspond to the sum of the current carriers contacting the conductor portions at that instant. The magnitude of the output waveform for any instant of time is therefore substantially proportional to the size of the area of the individual conductor portions being contacted at that instant by the current carriers. Accordingly, the contigurated areas of the individual conductors 70, 71 and 72 determines the magnitude of the output wave at any one instant ottime. Inasmuch as the sheet contacts the conductor areas succesively with time, a waveform is generated in output lines 75, 76 and 77 having a magnitude in accordance with their configurations, giving a desired output waveform corresponding thereto.

The particular waveforms generated by conductors 70, 71 and 72 are designated as n, x and y. The ,u voltage waveform is the unblanking voltage While the x voltage waveform is that voltage used to control the deection of the electron beam in the cathode ray tube 54 in the horizontal direction and the y voltage waveform is used to control the deflection of the electron beam in the vertical direction. Tfhe combination x-y voltages when applied to the electrostatic defiection plates 51 and 52 deliect the electron beam in the manner causing a character to be written or drawn on the screen of the tube. FIGURE 4 illustrates diagrammatically a graph of the respective p., x and y waveforms plotted in the relationship of time' versus voltage. The graphs are so arranged as to illustrate the manner in which the voltage waveforms control the potential on the deflection plates in the cathode ray tube 54 to dcect the electron beam in a manner to write or draw a character numeral 3 on the screen of the tube.

The unblanking voltage waveform a generated in conductor 70 is illustrated at 91 in FIGURE 4. This voltage waveform controls the electron beam generating means 53 of the cathode ray tube 54 permitting an electron beam to be generated and projected toward the screen only when the unblanking voltage is present. The x waveform form 92 received from conductor 71 controls the lhorizontal defiection of the electron beam by its variable magnitude being applied to the horizontal electrostatic deflection plates 51. The y voltage waveform 93 received from conductor 72 controls the vertical deection of the electron beam by controlling the potential on the vertical deflection plates 52. When all three waveforms are simultaneously supplied to the cathode ray tube 54 in the manner aforesaid, the electron beam is caused to be deected to predetermined positions on the screen of the tube, writing or drawing a character thereon in the shape of the numeral 3 illustrated at 94 in FIGURE 4. The unblanking voltage 91 turns on the beam generating means at the start of the x and y voltage waves and shuts off the electron beam at the finish of the x and y Voltage waves. Thus, the unblanking voltage assures that there is no continuation of the electron beam after the writing of the character on the screen.

While it is obvious that if no varying control potential remained on the electrostatic plates after the x and y voltages have terminated, then there would be no further writing influence on the beam. However, the beam generating and projecting unit is still operating, causing a spot on the screen and the unblanking voltage functions to synchronize extinguishment of the electron beam at the termination of the x and y waveforms. The unblanking voltage waveform originating in the waveform generator, as shown in FIGURE 4, has substantially a constant magnitude, inasmuch as the configurated conductor Ztl has a substantially rectangular shape. However, conductor 20 may have any configuration consonant with the waveform configuration output desired. Impressing an unblanking waveform having a variable magnitude or an interrupted magnitude on the beam generating means will permit the intensity of the electron beam to be selectively varied or interrupted. This allows shading or breaks in the characters displayed on the tube screen.

Referring again to FIGURE 1, the Waveform generators provide output waveforms n, x and y to common connecting lines 31, 32 and 33 when the waveform generators receive an interrogating pulse from their respective and gates. The waveforms are carried by the connecting lines 31, 32 and 33 to respective deection amplifiers 37, 38 and 39. These deflection amplifiers function to amplify the Waveform signals to provide a voltage output having a magnitude suficient to control the deiiection plates 51 and 52 in their deecting of the electronbeam.

The output of the amplifiers are connected to the electrostatic plates and the beam generating means 53.

The variable Vf voltage source 24 controls the speed at which a sheet of current carriers 73 traverses the semiconductor medium 80. This voltage may be selectively varied thereby varying the speed at which the sheet of current carriers 73 sweep the configurated conductor portions. Accordingly, should it be desirable to increase or decrease the length of the configurated lwaveforms relative to time, this may be accomplished by varying the variable voltage source 24. As shown in FIGURE 1, each of the waveform generators are connected to a single variable Vf voltage source. Accordingly, the time length of each of the waveforms generated by each of the units may be adjusted through a single control. However, a variable voltage source may also be provided for each of the individual waveform generators, or for a series of waveform generators, thereby permitting more individual control. Line 28 may be connected to other waveform generators which may be added to the display system.

The size gain control unit 36 includes a regulated voltage source which may be selectively varied. The voltage output of the control unit is supplied to each of the x and y deflection amplifier units. This voltage controls the degree of amplification of the x and y waveform signals by the deflection amplifier units. Since the size of the character images displayed on the tube screen depends upon the magnitude of the x and y voltage, the size of the displayed character images may be selectively varied by varying the output voltage from size control unit 36.

With respect to FIGURE 3, when an interrogation' pulse 79 is fed to the waveform generating unit, energy pulses of two different forms pass through the semi-conductor material. One energy pulse is the voltage waveforms resulting from the sheet of current carriers which progress through the semiconductor material at a delayed rate of Speed. The other energy pulse is an electrical current pulse which passes through the semi-conductor material at the conventional speed for the passage of electrical current through a conductor. The time required for the current carriers to traverse the semi-conductor medium exceeds that of the electrical pulse. Accordingly, in response to a group of incoming binary code, an electrical current pulse passes through the semiconductor medium and to the tube prior to the voltage waveforms. This electrical pulse is capable of momentarily unblanking the beam generating means causing an electron beam to be projected on the screen of the tube.

To prevent this momentary illumination of a spot on the tube screen, an overriding control pulse is supplied to the unblanking amplifier 37 via lines 20 through or gate 21 and line 43. Or gate 21 has an or gate circuit, which is well known in the art, being capable of providing an output pulse to line 43 in response to any positive pulse in any individual one or more of lines 20. Thus, when any incoming binary code is received by input lines A, B, C, D, E, or F, or gate 20 will receive at least one positive pulse through one of lines 2t) causing a pulse to reach the unblanking amplifier through line 43. This electrical pulse overrides the electrical pulse received by the unblanking amplifier through the waveform generator circuit, thereby precluding the unblanking of the beam generating means.

In summary, the operation of the system is as follows. Incoming binary code is received by lines A, B, C, D, E and F. The decoding unit tti decodes the incoming binary code and through one of the various and gates 22 provides a positive output pulse to a predetermined, individual one of the waveform generators. This interrogation pulse causes current carriers to traverse the semi-conductor medium of the waveform generators creating congurated waveforms to be supplied to output lines 31, 32 and 33. The output waveforms in lines 31, 32 and 33 are supplied to defiection amplifiers 37, 38 and 39 which amplify the respective waveforms for controlling the deflection means 50. The unblanlting amplifiersimultaneously supplies an output control waveform to the beam generating means causing an electron beam to be generated and preise-te towards the tube screen. The conguratcd voltage waveforms supplied to the respective vertical and horizontal deflection plates, so deilect the beam in its passage through the tube that a character is written or drawn on the screen of the tube. Deection plates 55 in response to the position deflection control signals from unit 44 establish the position on the screen of the tube dthat the character will be drawn or illustrated. Accordingly, the displayed character may be located at any position on the screen of the tube.

ln displaying7 coded information in the form of characters on the screen of a cathode ray tube, it is often desirable that the resulting display have a prearranged heading, generally known as a format, that may be constant for each series of character lill in information. Such headings generally find their greatest use where the information on the screen of the tube is transformed into a printed recording, or, is reduced to a permanent record through the use of photographic processes. For this purpose, the present invention provides a format waveform generator 4) which provides appropriately contigurated waveforms through position amplifiers di and 42 to the position deflection means 47. The waveforms from the format generator 40 provide a predetermined positioning of the characters generated in response to the incoming binary code.

inasmuch as the format generator positions a plurality of characters in a composite display, the format waveform has a longer time duration than the individual character waveforms. The format waveform generator functions in substantially the same manner as the character generator illustrated in FIGURE 3. As stated earlier, the semi-conductor material used in the waveform generators, may be of the N type, P type or intrinsic. In the specific embodiment shown in FIGURE 3, N type semi-conductive material was used. in using N type semiconductive material for the majority portion of the semiconductor blocks, the current carriers will be holes, while if P type material is used for the majority portion, the current carriers will be electrons. Electron current carriers will traverse the semi-conductor block in a shorter time interval than will hole current carriers. Therefore, the lmajority portion of character waveform generators may be made of P type semi-conductive material and the format waveform generator may be made of N type. This would permit a time differential between the format waveforms and the character waveforms. This time differential may be obtained in other ways, as for eX- ample, the format waveform generating unit may be made larger or have its inclined portion i3 positioned at a greater angle with the bottom surface 12. Also, the sweeping field resulting from variable voltage Vf may be varied to increase the time differential. In using the format waveform generator in the specific embodiment, the incoming interrogation pulse through line 58 will be synchronized with a predetermined group of incoming code signals to be received by the decoding unit. The aforesaid synchronized control will cause to be displayed on the screen of the tube 54 a logical character arrangement which will provide the desired format on the screen of the tube. This format may then be filled in with logical information from subsequently received binary code information.

The particular embodiments of the invention illustrated and described herein are illustrative only and the invention includes such other modifications and equivalents as may readily appear to those skilled in the art, within the scope of the appended claims.

I claim:

l. In a cathode ray system for displaying coded information in the form of character images comprising, at least one cathode ray tube having beam generating means for generating and projecting an electron bca-rn toward a screen and deflection means for dctiecting said beam. to predetermined positions on said screen, decoding means for receiving and decoding incoming groups of coded information, said decoding means providing output pulses 'to a single predetermined termina] means dependent upon the code group received, a plurality of waveform generating units each responsive to said output Vpulses for providing distinctively shaped output voltage waveforms to said deflection means, each waveform generating unitincluding a semi-conductor having distinctively shaped electrodes thereon, each of said electrodes providing output waveforms having configurations corresponding to said contiguration of said electrodes, stud detlection means in response to said waveforms causing said electron beam to draw on the screen of said tube a predetermined character corresponding to said incoming code.

2. In a display system wherein coded information having particular character designations are capable of being received and decoded by decoding means providing individual output pulses corresponding to individual character designations, and cathode ray means having beam generating means and deflection means and nal position deflection means for receiving waveforms corresponding to said character designations causing character images of said character designations to be displayed, the combination with said decoding means and said cathode ray means including a plurality of semi-conductor waveform generating units, each of said units in response to one of said individual output pulses being capable of providing output waveforms to said deflection means having predetermined configurations corresponding to said individual character designation and being capable of providing an unblanking waveform to said beam generating means, said output waveforms and said unblanking waveforms being synchronized in time causing said beam generating means to be selectively energized only when said output waveforms are received by said decction means, field means impressed across said waveform generating units for selectively varying the time length of said waveforms, amplifier means between said units and said deflection means for varying the magnitude of said output waveforms and said unblankiug waveforms, variable control means for providing selective positive control of said amplifier in varying said magnitude of said output waveforms and said unblanking waveforms by said amplifier means, other blanking control means for momentarily blanking said beam generating means when said decoding means receives said coded information, and other semiconductor waveform generating means providing output waveforms to said position deflection means in coordination with said incoming code for causing said position dcilection means to position a plurality of said character displays in a predetermined manner on said cathode ray means.

3. In a display system wherein coded information having lparticular character designations are capable of being received and decoded by a decoding means providing individual output pulses corresponding to individual character designations and cathode ray means having beam generating means and dccction means when receiving waveforms corresponding to said character designations causing character images of said character designations to be displayed, the combination with said decoding means and said cathode ray means including a plurality of semiconductor waveform generating means, each of said gen erating means in response to one of said individual output pulses being capable of providing output waveforms to said deflection means having predetermined configurations corresponding to said individual character designation and being capable of providing an unblanking waveform to said beam generating means, said output waveforms and said unblankiug waveforms being synchronized in time causing said beam generating means to be selectively energized only when said output waveforms are received by said deflection means, field means impressed across said waveform generating units for selectively varying the time length of said waveforms, amplifier means between said units and said deflection means for selectively varying the magnitude of said output waveforms and said unblanking waveforms, and another blanking control means for momentarily blanking ysaid beam generating means when said decoding means receives said coded information.

4. In a display system wherein coded information having particular character designations are capable of being received and decoded by a decoding means providing individual output pulses corresponding to individual character designations, and cathode ray means having beam generating means and deflection vmelansjand final position deflection means for receiving waveforms corresponding to said vcharacter designations causing character images of said character designations to be displayed, the com-bination with said decoding means and said cathode ray means including a plurality of semiconductor waveform generating units, each of said units comprising a single semiconductor body having a light doping of impurities therein, said body having configurated current collecting areas thereon, each of said areas being insulated from the other, injecting means positioned on the other end of said body for injecting current carriers therein in response to one of said output pulses, vvariable field means for causing said current carriers to drift at a predetermined speed in a direction toward said areas, said areas being positioned in a manner to be able to intercept portions of said current carriers successively with time, said areas having waveforms created therein in respon-se to said current carriers, at any given instant said waveforms having a magnitude correspondingto .the size of said areas being intersected by said current carriers during said instant, circuit means projecting said waveforms onto said deflection means and said beam generating means for causing to be displayed on said cathode ray means a character corresponding to said individual character designations, 'amplifier means between said units and said cathode ray means for selectively varying the magnitude of said output waveforms, separate blanking control means for momentarily blanking said beam generating means when said decoding means receives said coded information, and other semi-conductor waveform generating means providing output Waveforms to said position deflection means in coordination with said incoming code for causing said position deflection means to position a plurality of said character displays in a predetermined manner on said cathode ray means.

5. In a display system wherein coded information having particular character designations are capable of being received and decoded by a decoding means providing individual output pulses corresponding to individual character designations and cathode ray means having beam generating means and deflection means for receiving waveforms corresponding to said character designations causing character images of said character designations to be displayed, the combination with said decoding means and said cathode ray means including a plurality of semi-conductor waveform generating means, each of said generating means in response to one of said individual output pulses being capable of providing output waveforms to said deflection means having predetermined configurations corresponding to said individual character designation and being capable of providing an unblanking waveform to said beam generating means, -said output waveforms and said unblanking waveforms being synchronized in time causing said beam generating means to be selectively energized only when said output waveforms are received by said deflection means, field means impressed across said waveform generating units for selectively varying the time length of said waveforms, amplifier means between said units and said deflection means for selectively varying the magnitude of said output waveforms and said unf blanking waveforms.

6. In a system for displaying coded information in the form of characters on the screen of a cathode ray tube having deflection means, decoding means for receiving incoming coded information and providing output pulses with respect to the character designation of said coded in'- formation, means for generating and supplying to said deflection means a group of voltage waveforms, said generating means including a plurality of individual semi-conductor waveform generating units each having a character designation, each of said units in response to an interrogating pulse simultaneously providing a first configurated voltage waveform to the horizontal deflection plates of said deflection means and providing a second confgurated voltage waveform to the vertical deflection plates of said vdeflection means, said deflection means'in response yto said first and second waveforms acting to deflect said electron beam in a predetermined manner causing to be inscribed on said tscreen said designated character idenv.tified with said unit, said decoding means providing an 'output pulse to one of said units when said incoming code has a character designation corresponding to said character designation on said unit. l

,said areas being related to a particular character formation, each of said units being activated in response -to la Acorresponding one of said output' pulses to provide output signals at said electrodes whose waveform depends upon the predetermined configuration of the corresponding electrode, said cathode-ray display means including deflection means energized by said output signals of conilgurated waveform from an activated waveform generating unit for producing a display having a pattern dependent upon the waveform of said output signals.

8. A system as described in claim 7 including field means impressed across said waveform generating units for selectively varying the duration of said output signals.

9. In a system for displaying coded input information in the form of characters on the screen of an evacuated cathode-ray tube including therein electron beam deflection means, decoding means having separate output terminal means for each code group of input information, said decoding means providing output pulses at one of said terminal means which depends upon the particular code group being presented, a plurality of independently operating waveform generating units one for each of said code groups disposed externally of said cathode-ray tube, each of said units including a current carrying medium and electrode having conflgurated areas positioned on said medium, the configuration of each of said areas being related to a particular character formation, eacn of said units being activated in response to a corresponding one of said output pulses to provide output signals at said electrodes whose waveform depends upon the predetermined configuration of the corresponding electrode, said deflection means producing a display having a pattern dependent upon the waveform of the output signals in response to said output signals from an activated waveform generating unit.

l0. In a system for displaying coded input information in the form of characters on a cathode-ray display means, decoding means having separate output terminal means for each code group of input information, said decoding means providing output pulses at one of said terminal means which depends upon the particular code group being presented, a plurality of independently operating waveform generating units one for each of said code groups, each of said units including a current carrying medium and first and second electrodes having distinct configurated areas positioned on said medium, the con figuration of each of said areas being related to a particular character formation, each of said units being activated in response to a corresponding one of said output pulses to provide output signals at said first and second electrodes whose waveform depends upon the predetermined configuration of the corresponding electrode, said cathode-ray display means including first and second mutually perpendicular deflection means which in response to said output signals from said irst and second electrodes respectively of an activated waveform generating unit provide a display having a pattern dependent upon the waveform of said output signals.

1l. In a system for displaying coded input information in the form of characters on a cathode-ray display means, decoding means having separate output terminal means for each code group of input information, said decoding means providing output pulses at one of said terminal means which depends upon the particular code group being presented, a plurality of independently operating waveform generating units one for each of said code groups, each of said units including a current carrying medium and rst, second and third electrodes having distinct congurated areas positioned on said medium, the configuration of the areas of said irst and second electrodes being related to a particular character formation, each of said units being acivated in response to Va corresponding one of said output pulses to provide output signals at said first, second and third electrodes whose waveform depends upon the predetermined configuration of the corresponding electrode, said cathode-ray display means including rst and second mutually perpendicular deection means which in response to said output signals from said rst and second electrodes respectively of an activated waveform generating unit provide a display having a pattern dependent upon the waveform of said output signals, means responsive to the presence of any of said code groups for momentarily blanking said cathoderay display means, and means responsive to the output signal from said third electrode caused by passage of current carriers through said medium for overcoming the effect of said blanking control means.

l2. In a cathode ray system for displaying coded information in the form of characters upon an electroresponsive display, an electron beam :generating and projecting unit for generating an electron beam and projecting said beam towards said electro-responsive display, a beam deilection unit having distinct portions for deectng said electron beam in at least two mutually exclusive directions, decoding means for receiving and decoding incoming groups of coded information, said decoding means providing output pulses to a single predetermined terminal means dependent upon the code Agroup received, each of said code groups having a partieular character designation, a distinct waveform generating unit for each code group, each of said waveform generating units being energized in response to a corresponding one of said output pulses for providing at least two output voltage waveforms, the configuration of said waveforms from a given waveform generating unit being related to the configuration of the character designating the code group associated with the given waveform generating unit, means for supplying .said output voltage waveforms available from an energized generating unit to corresponding portions of said deflection unit for causing said electron beam to draw on said electro-responsive display a predetermined character image corresponding to said character designation.

Bardeen: Theory of Relation Between Hole Concentration and Characteristics of Germanium Point Contacts, October 1950 of the Bell System Technical Journal, pp. 469 to 495. 

